The present application claims priority under 35 U.S.C. xc2xa7 119 of German Patent Application No. 198 48 808.4, filed on Oct. 22, 1998, the disclosure of which is expressly incorporated by reference herein in its entirety.
1. Field of the Invention
The present invention relates to a process for severing a traveling material web, particularly a paper web in a winding device during reel spool changeover, in which a severing device is moved into the web travel path between a winding roll and an empty reel spool on the one side and the nearly full reel spool on the other side. The invention also relates to a device for performing such a process.
2. Discussion of Background Information
Winding devices of the type related to this invention are used at the end of a machine for manufacturing a material web where they facilitate continuous winding of the material web onto a reel spool. After a reel is finished, which is to say after a desired reel diameter has been reached, the material web must be severed and the full reel spool must be replaced by an empty reel spool, onto which the next reel is wound. On rare occasions, reel spool changeover can even take place when the reel has not yet reached the normally desired diameter.
A process and a device for performing such a reel spool changeover are known from WO 96/11868. To sever the paper web, this device uses a knife blade that traverses the entire width of the web and is moved from a neutral position to the web travel path of the paper web.
The present invention resides in a process of the type generally discussed above that provides a device for performing such a process.
This process provides a severing device that sequentially severs the material web across the width of the material web at several places so that, relative to the material web, the separation points lie along a line that runs at an angle to the web travel direction.
According to the invention, severing of the material web is performed in such a way that a cut edge results which is angled to the web travel direction. This cut edge can run at the same angle consistently across the entire width of the web. However, the cut edge can also take the form of a V-shape or a zigzag.
Severing the material web sequentially at several places along a line running at an angle to the web travel direction results in an especially advantageous, high-precision cut edge.
Preferably, the new web tail created in this manner is moved toward the empty reel spool by pressurized air. This ensures that the web tail is guided reliably to the empty reel spool.
To perform the process according to the invention, a device is used in one embodiment with a rotationally driven severing roll which moves from a neutral position to a cutting position and back, and which has on its roll sleeve several severing elements arranged along at least one spiral line.
When the severing roll is rotated, the severing elements arranged in a spiral on it engage with the material web one after the other. The circumferential velocity of the severing roll can equal the web travel velocity, but it can also be slower or faster than this velocity.
In addition, it is especially advantageous for the severing roll to be arranged on the side of the material web facing away from the empty reel spool. Thus, the movement of the severing roll between the neutral position and the severing position can take place without interfering with the empty reel spool.
In a further embodiment of the invention, air blast nozzles are provided on the roll. These are designed to aid in guiding the material web onto the empty reel spool. This reduces the risk of faulty guidance of the material web, increasing the reliability of the device correspondingly.
In one embodiment of the invention, the air blast nozzles can each be located directly adjacent to a severing element on the severing roll, and be supplied with pressurized air from the interior of the severing roll. In another embodiment of the invention, however, one or more air blast pipes with air blast nozzles can be provided on the outer surface of the roll sleeve of the severing roll. In this manner, the air volume is kept small, which results in a rapid pressure buildup and has the additional advantage that the air lost to leakage is reduced. The air blast pipes are preferably arranged parallel to the severing elements along a spiral line. Consequently, the pressurized air acts directly on the relevant cut edge.
According to one embodiment of the invention, the spiral line along which the severing elements are arranged on the severing roll can extend continuously across the entire width of the roll. This produces a straight cut edge diagonal to the web travel direction. According to another embodiment of the invention, however, the severing elements can also extend along two spiral lines running outward in opposite directions from a common point in the center of the severing roll. Because of the rotation of the severing roll this design generates a V-shaped cut edge, the peak of which points either in the web travel direction or in the opposite direction, depending on the arrangement of the spiral lines.
According to another embodiment of the invention, the severing elements are arranged along several spiral lines running alternately in opposite directions and connecting with one another across the width of the roll. This design produces a zigzag cut edge, the peaks of which again point either in the web travel direction or in the opposite direction, depending on the arrangement of the spiral lines.
In all cases, the spiral lines can encircle the circumference of the severing roll one or more times. However, it is also possible to arrange the spiral lines such that they encircle only part of the circumference of the severing roll. This arrangement has the advantage that the severing roll can initially be placed against the material web at its region that is free of severing elements. The synchronization of this placement and the rotation of the severing roll is thus simplified.
According to another embodiment of the invention, control structure is provided through which, in sequence, the severing roll can be set to rotate, the air blast nozzles can be supplied with pressurized air, and the severing roll can be moved to its severing position, such that the delivery of pressurized air to the air blast nozzles preferably occurs immediately before the severing roll penetrates the material web. In a corresponding fashion, the process is reversed; the severing roll is moved back to its starting position, the rotation of the severing roll is stopped, and the air supply is shut off. In this way, the severing process can advantageously be automated.
According to another embodiment of the invention, control structure is provided which ensures that the forwardmost severing element when viewed in the rotational direction of the severing roll, is the first to act upon the material web. Thus, the control structure is used to ensure that complete and clean severing takes place across the entire width of the material web.
The process according to the invention can also be performed with a device which has a supporting beam extending essentially across the width of the material web and carrying the severing elements. The severing elements are moveable from a neutral position to a severing position and back, wherein the severing elements are arranged such that they engage the material web one after another when the supporting beam is moved into the severing position. The severing elements are arranged on the supporting beam to produce the desired shape of the cut edge. Thus, the severing elements can be arranged on the supporting beam along a line running continuously across the entire web width at an angle to the web travel direction.
According to another embodiment of the invention, the severing elements on the supporting beam can extend along two lines running outward in opposite directions from a common point in the center of the web. According to yet another embodiment of the invention, the severing elements can be arranged on the supporting beam in a zigzag perpendicular to the web travel direction. Since the severing elements engage with the material web sequentially when the supporting beam is moved from the neutral position to the severing position, the desired shape of the cut edge can be produced in this manner.
According to another embodiment of the invention, the supporting beam is swivel-mounted such that the severing elements act upon the material web one after another starting with the forwardmost severing element in the web travel direction. This design ensures that complete and clean severing takes place across the entire width of the material web.
According to another embodiment of the invention, air blast nozzles are provided on the supporting beam to aid in guiding the material web onto the empty reel spool. In this manner, the material web is blown onto the empty reel spool directly at the cut edge.
The process according to the invention can additionally be performed with a device which has a carrier extending transversely across the web width upon which several severing elements are distributed next to one another across the web width, and which causes the severing elements to act on the material web in time sequenced fashion relative to one another. In this variation, the carrier with the severing elements is brought to a fixed severing position. The production of several separation points across the web width is then accomplished in that the severing elements are activated in sequence by appropriate structure.
Several blades are arranged on the carrier such that they can swivel between a neutral position, in which the blades extend in the web travel direction next to the material web, and a severing position in which the blades cross the web travel path. The desired separation points are provided across the web width through the time-sequenced swiveling of the blades into the web travel path. The shape of the cut edge can be produced as desired through appropriate time sequenced activation of the blades. Hence this variation can also produce a continuous diagonal cut edge, a V-shaped cut edge and a zigzag cut edge.
The blades are activated by a rotationally driven camshaft mounted beneath the blades, where the cams raise or lower the blades as a function of the rotational position of the camshaft.
According to another embodiment of the invention, air blast nozzles are arranged on the carrier. In particular, the air blast nozzles are each located between two severing elements. Again, in this manner, the newly formed web tail is blown directly at the cut edge.
In all variations, blades are provided as severing elements, where the blades can have a straight or a serrated cutting edge. Good severing results can be achieved using blades as severing elements. However, the severing elements can also be laser beams or pressurized water jets, or other severing elements.
There is disclosed herein, a process for severing a traveling material web, at reel spool changeover, in a winding device. The process comprises moving a severing device into the web travel path between a winding roll and an empty reel spool on one side and a reel spool carrying a reel formed on the other side of the device and severing the material web across the width of the material web at several places, sequentially by the severing device, at separation points which lie along a line that runs at an angle to a travel direction of the web.
The material web may comprise a paper web. The line for the separation points runs at substantially the same angle across the entire width of the web. Alternatively, the line runs in the shape of an upside-down V from a center of the web to the edges of the material web. In yet another alternative, the line runs as a zigzag across a width of the web.
The process according to the invention further comprises moving, by way of pressurized air, a new web tail created by the severing process toward the empty reel spool. The severing is performed by moving a rotationally driven severing roll from a neutral position to a cutting position and back, the severing roll having a sleeve on which several severing elements are arranged along at least one spiral line. The rotational velocity of the severing roll is adjusted to be at least approximately equal to the travel velocity of the web.
The severing roll is arranged on a side of the material web facing away from the empty reel spool. The material web is guided onto the empty reel spool by way of blowing air through air blast nozzles provided on the severing roll. Pressurized air is supplied from the interior of the severing roll to the air blast nozzles, each of the blast nozzles being located directly adjacent to a severing element.
The material web is guided onto the empty reel spool by way of blowing air through at least one air blast pipe and air blast nozzles provided on the outer surface of the roll sleeve of the severing roll. The at least one air blast pipe is arranged parallel to the severing elements along a spiral line. Alternatively, the severing elements are arranged along at least one spiral line which extends continuously across substantially the entire width of the severing roll. As a further alternative, the severing elements are arranged along two spiral lines running outwardly in opposite directions from a common point in a center of the severing roll.
The spiral lines encircle only part of the circumference of the severing roll, another part of the circumference of the severing roll being free of severing elements. The severing elements are arranged along several spiral lines running alternately in opposite directions and connecting with one another.
The severing of the web is performed sequentially by rotating the severing roll, delivering pressurized air to the blast nozzles and moving the severing roll to its severing position, wherein delivery of pressurized air to the blast nozzles occurs immediately before the severing roll penetrates the material web.
A controller ensures that a forwardmost severing element of each spiral line, when viewed in the rotational direction of the severing roll, is the first to act upon the material web.
According to another aspect of the invention, a support beam, extending essentially across the width of the material web and carrying the severing elements, is moved from a neutral position to a severing position and back, wherein the severing elements are arranged such that they engage the material web one after another when the supporting beam is moved into the severing position. The supporting beam is arranged on the side of the material web facing away from the empty reel spool.
According to the invention, the severing elements are arranged on the supporting beam along a line running continuously across substantially the entire width of the web at an angle to the web travel direction. Alternatively, the severing elements on the supporting beam extend along two lines running outward in opposite directions from a center of the web. In accordance with a further embodiment, the severing elements on the supporting beam are arranged along a zigzag line running perpendicular to the travel direction of the web.
The supporting beam is swivel-mounted such that the severing elements act upon the material web one after another starting with the forwardmost severing element in the travel direction of the web. Air blast nozzles are provided on the supporting beam.
According to an aspect of the invention, the severing elements are controlled in a manner to have them act on the material web at intervals relative to one another and wherein a carrier extends transversely across the width of the web, the carrier having several severing elements distributed next to one another across the web width. Several blades are arranged on the carrier in a manner permitting them to swivel between a neutral position, in which the blades extend in the travel direction of the web next to the material web, and a severing position in which the blades cross the travel path of the web.
A camshaft mounted beneath the blades is rotationally driven. The blades are raised or lowered as a function of the rotational position of cams on the camshaft. The carrier is arranged on the side of the material web facing away from the empty reel spool. Air blast nozzles are provided on the carrier to aid in guiding the material web onto the empty reel spool.
Air blast nozzles are each located between two severing elements. The severing elements comprise blades which have a straight cutting edge or a serrated cutting edge.
The invention further contemplates a winding device for a material web, e.g., a paper web, comprising a winding roll, an empty reel spool on one side of the winding roll and a reel spool carrying a reel on another side of the winding roll. A severing device for severing the material web, at reel spool changeover, is moved into the web travel path between the winding roll and the empty reel spool. The material web is severed across the width thereof at several places sequentially by the severing device, at separation points which lie along a line that runs at an angle to the travel direction of the web. The line runs at substantially the same angle across the entire width of the web. Alternatively, the line runs in the shape of an upside-down V from a center of the web to the edges of the material web. In a further embodiment, yet, the line runs as a zigzag across a width of the web. A source of pressurized air moves a new web tail created by the severing process toward the empty reel spool.
According to an aspect of the invention, the severing device comprises a rotationally driven severing roll moving from a neutral position to a cutting position and back, the severing roll having a sleeve on which several severing elements are arranged along at least one spiral line. An adjustment mechanism is provided for adjusting the rotational velocity of the severing roll to be at least approximately equal to the travel velocity of the web. The severing roll is arranged on a side of the material web facing away from the empty reel spool.
Air blast nozzles are provided on the severing roll for guiding the material web onto the empty reel spool by blowing air thereon. A pressurized air connection is made from the interior of the severing roll to the air blast nozzles, each of the blast nozzles being located directly adjacent to a severing element.
At least one air blast pipe and air blast nozzles are provided on the outer surface of the roll sleeve of the severing roll for guiding the material web onto the empty reel spool by way of blowing air thereon. At least one air blast pipe is arranged parallel to the severing elements along a spiral line.
According to one embodiment of the invention, the severing elements are arranged along at least one spiral line which extends continuously across substantially the entire width of the severing roll.
According to another embodiment of the invention, the severing elements are arranged along two spiral lines running outwardly in opposite directions from a common point in a center of the severing roll.
According to yet another embodiment of the invention, the severing elements are arranged along several spiral lines running alternately in opposite directions and connecting with one another.
The spiral lines encircle only part of the circumference of the severing roll, another part of the circumference of the severing roll being free of severing elements.
A controller causes sequential rotation of the severing roll, pressurized air delivery to the blast nozzles and movement of the severing roll to its severing position, wherein delivery of pressurized air to the blast nozzles occurs immediately before the severing roll penetrates the material web.
A controller ensures that a forwardmost severing element of each spiral line, when viewed in the rotational direction of the severing roll, is the first to act upon the material web.
A supporting beam extends essentially across the width of the material web and carries the severing elements, from a neutral position to a severing position and back, wherein the severing elements are arranged such that they engage the material web one after another when the supporting beam is moved into the severing position.
The supporting beam is arranged on a side of the material web facing away from the empty reel spool.
The severing elements are arranged on the supporting beam along a line running continuously across substantially the entire width of the web at an angle to the web travel direction. Alternatively, the severing elements on the supporting beam extend along two lines running outward in opposite directions from a center of the web. Further yet, the severing elements on the supporting beam are arranged along a zigzag line running perpendicular to the travel direction of the web.
The supporting beam is swivel-mounted such that the severing elements act upon the material web one after another starting with the forwardmost severing element in the travel direction of the web.
Air blast nozzles are provided on the supporting beam.
A controller is provided for controlling the severing elements in a manner to have them act on the material web at intervals relative to one another. A carrier extends transversely across the width of the web, the carrier having several severing elements distributed next to one another across the web width.
Several blades are arranged on the carrier in a manner permitting them to swivel between a neutral position, in which the blades extend in the travel direction of the web next to the material web, and a severing position in which the blades cross the travel path of the web.
According to another aspect of the invention, there is provided a rotationally driven camshaft including cams mounted beneath the blades, the blades being raised or lowered as a function of the rotational position of the cams.
The carrier is arranged on the side of the material web facing away from the empty reel spool.
Air blast nozzles are provided on the carrier for helping to guide the material web onto the empty reel spool. The air blast nozzles are each located between two severing elements, which may comprise blades. The blades have a straight cutting edge, or they may have a serrated cutting edge.
The winding device according to the invention comprises a winding roll, an empty reel spool on one side of the winding roll and a reel spool carrying a reel on another side of the winding roll. A severing device for severing the material web at reel spool changeover is moved into the web travel path between the winding roll and the empty reel spool. The material web is severed across the width thereof at several places sequentially by the severing device, at separation points which lie along a line that runs at an angle to the travel direction of the web. A source of pressurized air moves a new web tail created by the severing process toward the empty reel spool. The severing device comprises a rotationally driven severing roll moving from a neutral position to a cutting position and back, the severing roll having a sleeve on which several severing elements are arranged along at least one spiral line. An adjustment mechanism adjusts the rotational velocity of the severing roll to be at least approximately equal to the travel velocity of the web. The severing roll is arranged on a side of the material web facing away from the empty reel spool. Air blast nozzles provided on the severing roll guide the material web onto the empty reel spool by blowing air thereon. A pressurized air connection is provided from the interior of the severing roll to the air blast nozzles, each of said blast nozzles being located directly adjacent to a severing element. At least one air blast pipe and air blast nozzles are provided on the outer surface of the roll sleeve of the severing roll for guiding the material web onto the empty reel spool by way of blowing air thereon. A controller causes sequential rotation of the severing roll, pressurized air delivery to the blast nozzles and movement of the severing roll to its severing position. Delivery of pressurized air to the blast nozzles occurs immediately before the severing roll penetrates the material web. A controller ensures that a forwardmost severing element of each spiral line, when viewed in the rotational direction of the severing roll, is the first to act upon the material web. A supporting beam extends essentially across the width of the material web and carries the severing elements, from a neutral position to a severing position and back. The severing elements are arranged such that they engage the material web one after another when the supporting beam is moved into the severing position. The supporting beam is arranged on a side of the material web facing away from the empty reel spool.
Exemplary embodiments of the invention are depicted in the drawings and described below.
Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawings.